Templated Anisotropic Analyses of the LISA Galactic Foreground

Abstract

The Laser Interferometer Space Antenna (LISA) will feature a prominent anisotropic astrophysical stochastic gravitational wave signal, arising from the tens of millions of unresolved mHz white dwarf binaries in the Milky Way: the Galactic foreground. While proper characterization of the Galactic foreground as a noise source will be crucial for every LISA science goal, it is extremely scientifically interesting in its own right, comprising -- along with $\sim 10^4$ resolvable white dwarf binaries -- a complete sample of every mHz white dwarf binary in our Galaxy. We present a novel Bayesian analysis of the LISA Galactic foreground that directly treats its anisotropy via astrophysically-motivated templates, allowing for a direct connection between the observed time-modulation of the foreground amplitude and the underlying spatial distribution of the Milky Way. We validate the efficacy of this approach via simulated data and show that it is able to accurately recover the foreground spectrum in the presence of LISA instrumental noise.

18 pages, 11 figures

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Cited by in corpus (4)

• Muffled Murmurs: Environmental effects in the LISA stochastic signal from stellar-mass black hole binaries
• Test for LISA foreground Gaussianity and stationarity: galactic white-dwarf binaries
• Gravitational wave energy spectral density properties from BPASS Galactic binary population in the Milky Way galaxy
• Searching Stochastic Gravitational Wave Background Landscape Across Frequency Bands